Question
I was wondering if it is ok to mix water with amonium nitrate to spray on my mondo grass instead of using just some multi-purpose fertilizer, and if so what would you suggest for a ratio?
Thank you
  Mike

Answer
The problem with ammonium nitrate is that it does not contain any phosphorous and potassium which is needed. First of all, I don't understand why you want to dissolve the fertilizer in water first. I would just take a small amount between the fingers and distribute it around the grass in a circle, and then water in.

If you insist on disolving with water then I would use a 200-400 ppm solution: 1/2-1 tsp per gallon of water.

A better solutin would be a 20-10-10 fertilizer (primarily nitrogen, but also some phosphorous and potassium).